This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A210108 #11 Jul 13 2013 12:04:24 %S A210108 1,1,2,4,8,10,34,68,94,104,496,992,1420,1712,1816,11056,22112,32176, %T A210108 40256,45496,47312,349504,699008,1026400,1309568,1528384,1666688, %U A210108 1714000,14873104,29746208,43920304,56696384,67419664,75523808,80571184,82285184,819786496 %N A210108 Left half of Poupard's triangle, A008301. %H A210108 Reinhard Zumkeller, <a href="/A210108/b210108.txt">Rows n=0..120 of triangle, flattened</a> %F A210108 T(n,k) = A008301(n,k), 0 <= k <= n. %o A210108 (Haskell) %o A210108 a210108 n k = a210108_tabl !! n !! k %o A210108 a210108_row n = a210108_tabl !! n %o A210108 a210108_tabl = zipWith take [1..] a008301_tabf %Y A210108 Cf. A002105 (left edge), A005799 (right edge); A210111. %K A210108 nonn,tabl %O A210108 0,3 %A A210108 _Reinhard Zumkeller_, Mar 17 2012